I found this study to be very intriguing. In my view it explains a lot about the problem of PTSD, as well as why our "gut" (lower brain) often tells us important information well before the conscious brain figures it out. It also blows holes in some popular beliefs concerning therapy for people who have gone through traumatic events.
From the Proceedings of the National Academy of Sciences...
From the WSJ...Sustained experience of emotion after loss of memory in patients with amnesia
Justin S. Feinsteina,b,1, Melissa C. Duffa,c, and Daniel Tranela,b
a - Division of Cognitive Neuroscience, Department of Neurology, University of Iowa College of Medicine,
b - Department of Psychology, and
c - Department of Communication Sciences and Disorders, University of Iowa, Iowa City, IA 52242-1053
Edited by Marcus E. Raichle, Washington University, St. Louis, MO, and approved March 17, 2010 (received for review December 9, 2009)
Abstract
Can the experience of an emotion persist once the memory for what induced the emotion has been forgotten? We capitalized on a rare opportunity to study this question directly using a select group of patients with severe amnesia following circumscribed bilateral damage to the hippocampus. The amnesic patients underwent a sadness induction procedure (using affectively-laden film clips) to ascertain whether their experience of sadness would persist beyond their memory for the sadness-inducing films. The experiment showed that the patients continued to experience elevated levels of sadness well beyond the point in time at which they had lost factual memory for the film clips. A second experiment using a happiness induction procedure yielded similar results, suggesting that both positive and negative emotional experiences can persist independent of explicit memory for the inducing event. These findings provide direct evidence that a feeling of emotion can endure beyond the conscious recollection for the events that initially triggered the emotion.
- BillEmotions can outlast the memory of the facts on which those feelings are based, according to a study of amnesiac patients in Proceedings of the National Academy of Sciences. Five patients with severe anterograde amnesia, which largely prevents the creation of new memories, watched a 19-minute video of film clips about death and loss. (The clips included scenes from "Sophie's Choice" and "Forrest Gump.") Several times during the study, researchers asked the subjects how they felt. Five to 10 minutes after the final scene, the amnesiacs remembered nearly nothing they had seen. They were asked to rate their emotions on several scales, including to what degrees they felt happy, sad, amused and "bad/unpleasant" versus "good/pleasant". The responses showed that the amnesiacs' negative emotions were stronger and lasted longer, than a control group of subjects who had no brain damage. The researchers repeated the experiment with humorous film clips, finding that positive emotions also outlasted specific memories. The results contradict the popular concept that "erasing" painful memories can ease the distress associated with those memories, the researchers said.